(1) Field of the Invention
The present invention relates to an electrode for use with an electrosurgical cutting and cauterizing instrument. In particular, the present invention relates to an electrosurgical cutting and cauterizing electrode that is comprised of several blade sections that are connected, end-to-end, in a longitudinal sequence. The sequential blade sections are interconnected by frangible connections that enable breaking away a used blade section at an end of the electrode and exposing a new blade section for use.
(2) Description of the Related Art
Electrosurgical instruments of the prior art that are used to both cut tissue and cauterize or coagulate open blood vessels commonly comprise a single electrode that is removably mounted in a scalpel handle. The scalpel handle is electrically connected by several conductors to a separate electrical power source. The scalpel handle conductors include a therapeutic current conductor between the handle and the power source, and two signal current conductors between the therapeutic current conductor in the handle and the power source. The two signal conductors complete two signal circuits to the power source that control the power source to produce a continuous sine wave signal for cutting purposes, or a pulsing signal for coagulating purposes. A grounding plate or pad on which a patient lays is connected by a further conductor to the power source.
The scalpel handle includes a socket for releasably receiving the prior art electrode. The socket is connected by the therapeutic current conductor to the separate power source. The prior art scalpel handle is also commonly provided with two separate manually actuated switches. The switches control connection of the electrode socket and the therapeutic current conductor to the two signal current conductors communicating the handle with the separate power source, and selectively control the supply of the continuous sine wave signal or the pulsing signal from the power source to the socket. By selectively actuating the two switches, the electrode inserted in the handle socket is subjected to either the continuous sine wave signal or the pulsing signal supplied to the socket by the separate power source. Electrosurgical instruments of this type are disclosed in U.S. Pat. No. 4,427,006, and U.S. Pat. No. 4,112,950.
Prior art electrodes are commonly configured from a flat strip of surgical steel. The electrodes are stamped from the strips in the configuration of a flat elongated member having beveled longitudinal edges that lead up to a rounded, blunt distal end. When subjected to the continuous current supplied by the separate power source, the beveled edges of the electrode are used in making incisions in tissue and cauterizing smaller blood vessels as incisions are made. When subjected to the second pulsing current supplied by the separate power source, the blunt, rounded end of the electrode is used in coagulating larger blood vessels.
Prior art electrodes have been found to be disadvantaged in that, after a relatively short period of use, blood begins to coagulate on the cutting edges and the blunt end of the electrode. Coagulation of blood on the electrode necessitates stopping surgery and cleaning the electrode several times during the course of one surgical operation, or stopping surgery so that the used electrode may be replaced with a new electrode. Both procedures require stopping surgery for a certain period of time while the electrode is cleaned or replaced.